Siberry George K, Tekle Tsigereda, Carroll Karen, Dick James
Division of Pediatric Infectious Diseases, Department of Pediatrics, Johns Hopkins Hospital, Baltimore, Maryland 21287, USA.
Clin Infect Dis. 2003 Nov 1;37(9):1257-60. doi: 10.1086/377501. Epub 2003 Oct 3.
We report a case of a surgical site infection caused by clindamycin-susceptible, erythromycin-resistant methicillin-resistant Staphylococcus aureus (MRSA) that did not respond to treatment with clindamycin. The MRSA isolate obtained after treatment was resistant to clindamycin but was found to be identical by pulsed-field gel electrophoresis to the clindamycin-susceptible isolate obtained before treatment. A post hoc erythromycin-induction test (D test) confirmed the presence of in vitro inducible macrolide-lincosamide-streptogramin B resistance (iMLS) in the pretreatment isolate. Erythromycin induction testing confirmed in vitro iMLS in 90 (56%) of 161 erythromycin-resistant, clindamycin-susceptible clinical S. aureus isolates overall and in a significantly higher proportion (78%) of methicillin-susceptible S. aureus isolates from pediatric patients. Our clinical laboratory currently tests all S. aureus isolates for iMLS before reporting clindamycin susceptibility.
我们报告了1例由对克林霉素敏感、对红霉素耐药的耐甲氧西林金黄色葡萄球菌（MRSA）引起的手术部位感染，该感染对克林霉素治疗无反应。治疗后获得的MRSA分离株对克林霉素耐药，但通过脉冲场凝胶电泳发现其与治疗前获得的对克林霉素敏感的分离株相同。事后红霉素诱导试验（D试验）证实治疗前分离株存在体外诱导型大环内酯 - 林可酰胺 - 链阳菌素B耐药（iMLS）。红霉素诱导试验证实，在总共161株对红霉素耐药、对克林霉素敏感的临床金黄色葡萄球菌分离株中，有90株（56%）存在体外iMLS，而在儿科患者的甲氧西林敏感金黄色葡萄球菌分离株中，这一比例显著更高（78%）。我们的临床实验室目前在报告克林霉素敏感性之前，会对所有金黄色葡萄球菌分离株进行iMLS检测。
